HKEY_CURRENT_USER\software\policies\microsoft\office\16.0\excel\security\protectedview

Always open untrusted database files in Protected View
- HKEY_CURRENT_USER\software\policies\microsoft\office\16.0\excel\security\protectedview\enabledatabasefileprotectedview
Always open untrusted text-based files in Protected View
- HKEY_CURRENT_USER\software\policies\microsoft\office\16.0\excel\security\protectedview\enableforeigntextfileprotectedview
Turn off Protected View for attachments opened from Outlook
- HKEY_CURRENT_USER\software\policies\microsoft\office\16.0\excel\security\protectedview\disableattachmentsinpv
Do not open files from the internet zone in Protected View
- HKEY_CURRENT_USER\software\policies\microsoft\office\16.0\excel\security\protectedview\disableinternetfilesinpv
Do not open files in unsafe locations in Protected View
- HKEY_CURRENT_USER\software\policies\microsoft\office\16.0\excel\security\protectedview\disableunsafelocationsinpv
Open files on local Intranet UNC in Protected View
- HKEY_CURRENT_USER\software\policies\microsoft\office\16.0\excel\security\protectedview\disableintranetcheck